Evaluation of liquid and powdered forms of polyclonal antibody preparation against Streptococcus bovis and Fusobacterium necrophorum in cattle adapted or not adapted to highly fermentable carbohydrate diets

Objective

Feed additives that modify rumen fermentation can be used to prevent metabolic disturbances such as acidosis and optimize beef cattle production. The study evaluated the effects of liquid and powdered forms of polyclonal antibody preparation (PAP) against Streptococcus bovis and Fusobacterium necrophorum on rumen fermentation parameters in ruminally cannulated non-lactating dairy cows that were adapted or unadapted to a high concentrate diet.

Methods

A double 3×3 Latin square design was used with three PAP treatments (control, powdered, and liquid PAP) and two adaptation protocols (adapted, unadapted; applied to the square). Adapted animals were transitioned for 2 weeks from an all-forage to an 80% concentrate diet, while unadapted animals were switched abruptly.

Results

Interactions between sampling time and adaptation were observed; 12 h after feeding, the adapted group had lower ruminal pH and greater total short chain fatty acid concentrations than the unadapted group, while the opposite was observed after 24 h. Acetate:propionate ratio, molar proportion of butyrate and ammonia nitrogen concentration were generally greater in adapted than unadapted cattle up to 36 h after feeding. Adaptation promoted 3.5 times the number of Entodinium protozoa but copy numbers of Streptococcus bovis and Fibrobacter succinogens genes in rumen fluid were not affected. However, neither liquid nor powdered forms of PAP altered rumen acidosis variables in adapted or unadapted animals.

Conclusion

Adaptation of cattle to highly fermentable carbohydrate diets promoted a more stable ruminal environment, but PAP was not effective in this study in which no animal experienced acute or sub-acute rumen acidosis.

An improvement of real-time polymerase chain reaction system based on probe modification is required for accurate detection of African swine fever virus in clinical samples in Vietnam

Objective

The rapid and reliable detection of the African swine fever virus (ASFV) plays an important role in emergency control and preventive measures of ASF. Some methods have been recommended by FAO/OIE to detect ASFV in clinical samples, including real-time polymerase chain reaction (PCR). However, mismatches in primer and probe binding regions may cause a false-negative result. Here, a slight modification in probe sequence has been conducted to improve the qualification of real-time PCR based on World Organization for Animal Health (OIE) protocol for accurate detection of ASFV in field samples in Vietnam.

Methods

Seven positive confirmed samples (four samples have no mismatch, and three samples contained one mutation in probe binding sites) were used to establish novel real-time PCR with slightly modified probe (Y = C or T) in comparison with original probe recommended by OIE.

Results

Both real-time PCRs using the OIE-recommended probe and novel modified probe can detect ASFV in clinical samples without mismatch in probe binding site. A high correlation of cycle quantification (Cq) values was observed in which Cq values obtained from both probes arranged from 22 to 25, suggesting that modified probe sequence does not impede the qualification of real-time PCR to detect ASFV in clinical samples. However, the samples with one mutation in probe binding sites were ASFV negative with OIE recommended probe but positive with our modified probe (Cq value ranked between 33.12–35.78).

Conclusion

We demonstrated for the first time that a mismatch in probe binding regions caused a false negative result by OIE recommended real-time PCR, and a slightly modified probe is required to enhance the sensitivity and obtain an ASF accurate diagnosis in field samples in Vietnam.

In Vitro Osteogenic Differentiation Enhanced by Zirconia Coated with Bone Morphogenetic Protein-2

In this study we report on the effectiveness of click chemistry-enhanced zirconium dioxide (ZrO2-3) for the immobilization of biomolecules, and the enhancement of osteoblastic differentiation of MC3T3-E1 cells by bone morphogenetic protein-2 (BMP-2) immobilized on ZrO2-6. The surfaces of ZrO2-1 through 6 were characterized by scanning electron microscopy (SEM), static contact angles, and X-ray photoelectron spectroscopy (XPS) measurements. The results from these tests indicated that ZrO2-1 was successfully surface-modified via click chemistry (ZrO2-3). Through quantitative analysis of heparin immobilized on ZrO2-5, we found that ZrO2-3 was a useful tool for immobilizing biomolecules such as heparin. Release tests of BMP-2 from ZrO2-6 showed well-controlled release kinetics over a period of 28 days. MC3T3-E1 cell proliferation tests indicated that ZrO2-6 was highly biocompatible with these cells. Through In Vitro tests such as alkaline phosphatase (ALP) activity, calcium deposition, and real-time polymerase chain reaction (real-time PCR), we found that ZrO2-6 was a useful tool for enhancing osteoblastic differentiation of MC3T3-E1 cells.

The relationship between peripheral blood mononuclear cells telomere length and diet - unexpected effect of red meat

BACKGROUND

Repeated nucleotide sequences combined with proteins called telomeres cover chromosome ends and dictate cells lifespan. Many factors can modify telomere length, among them are: nutrition and smoking habits, physical activities and socioeconomic status measured by education level. The aim of the study was to determine the influence of above mentioned factors on peripheral blood mononuclear cells telomere length.

METHODS

Study included 28 subjects (seven male and 21 female, age 18-65 years.), smokers and non-smokers without any serious health problems in past and present. Following a basic medical examination, patients completed the food frequency questionnaire with 17 foods and beverages most common groups and gave blood for testing. PBMC telomere length were measured with qualitative real-time Polymerase Chain Reaction (rtPCR) method and expressed as a T/S ratio.

RESULTS

Among nine food types (cereal, fruits, vegetables, diary, red meat, poultry, fish, sweets and salty snacks) and eight beverages (juices, coffee, tea, mineral water, alcoholic- and sweetened carbonated beverages) only intake of red meat was related to T/S ratio. Individuals with increased consumption of red meat have had higher T/S ratio and the strongest significant differences were observed between consumer groups: "never" and "1-2 daily" (p = 0.02). Smoking habits, physical activity, LDL and HDL concentrations, and education level were not related to telomere length, directly or as a covariates.

CONCLUSIONS

Unexpected correlation of telomere length with the frequency of consumption of red meat indicates the need for further in-depth research and may undermine some accepted concepts of adverse effects of this diet on the health status and life longevity.

Effects of Coconut Materials on In vitro Ruminal Methanogenesis and Fermentation Characteristics

The objective of this study was to evaluate the in vitro effects of coconut materials on ruminal methanogenesis and fermentation characteristics, in particular their effectiveness for mitigating ruminal methanogenesis. Fistulated Holstein cows were used as the donor of rumen fluid. Coconut materials were added to an in vitro fermentation incubated with rumen fluid-buffer mixture and timothy substrate for 24 h incubation. Total gas production, gas profiles, total volatile fatty acids (tVFAs) and the ruminal methanogens diversity were measured. Although gas profiles in added coconut oil and coconut powder were not significantly different, in vitro ruminal methane production was decreased with the level of reduction between 15% and 19% as compared to control, respectively. Coconut oil and coconut powder also inhibited gas production. The tVFAs concentration was increased by coconut materials, but was not affected significantly as compared to control. Acetate concentration was significantly lower (p<0.05), while propionate was significantly higher (p<0.05) by addition of the coconut materials than that of the control. The acetate:propionate ratio was significantly lowered with addition of coconut oil and coconut powder (p<0.05). The methanogens and ciliate-associated methanogens in all added coconut materials were shown to decrease as compared with control. This study showed that ciliate-associated methanogens diversity was reduced by more than 50% in both coconut oil and coconut powder treatments. In conclusion, these results indicate that coconut powder is a potential agent for decreasing in vitro ruminal methane production and as effective as coconut oil.

Molecular analysis of oral bacteria in dental biofilm and atherosclerotic plaques of patients with vascular disease

BACKGROUND

Oral bacteria have been detected in atherosclerotic plaques at a variable frequency; however, the connection between oral health and vascular and oral bacterial profiles of patients with vascular disease is not clearly established. The aim of this study was to evaluate the presence of oral bacterial DNA in the mouth and atherosclerotic plaques, in addition to assessing the patients' caries and periodontal disease history.

METHODS

Thirty samples of supragingival and subgingival plaque, saliva and atherosclerotic plaques of 13 patients with carotid stenosis or aortic aneurysm were evaluated, through real-time polymerase chain reaction, for the presence of Streptococcus mutans (SM), Prevotella intermedia (PI), Porphyromonas gingivalis (PG) and Treponema denticola (TD). All patients were submitted to oral examination using the DMFT (decayed, missing and filled teeth) and PSR (Periodontal Screening and Recording) indexes. Histopathological analysis of the atherosclerotic plaques was performed.

RESULTS

Most of the patients were edentulous (76.9%). SM, PI, PG and TD were detected in 100.0%, 92.0%, 15.3% and 30.7% of the oral samples, respectively. SM was the most prevalent targeted bacteria in atherosclerotic plaques, detected in 100% of the samples, followed by PI (7.1%). The vascular samples were negative for PG and TD. There was a statistically significant difference (p<0.05) between the presence of PG and TD in the oral cavity and vascular samples.

CONCLUSION

SM was found at a high frequency in oral and vascular samples, even in edentulous patients, and its presence in atherosclerotic plaques suggests the possible involvement of this bacterium in the disease progression.